/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * 
 */

package org.apache.jorphan.collections;

import java.io.Serializable;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.apache.jorphan.logging.LoggingManager;
import org.apache.jorphan.util.JOrphanUtils;
import org.apache.log.Logger;

/**
 * Use this class to store database-like data. This class uses rows and columns
 * to organize its data. It has some convenience methods that allow fast loading
 * and retrieval of the data into and out of string arrays. It is also handy for
 * reading CSV files.
 * 
 */
public class Data implements Serializable {
	private static final Logger log = LoggingManager.getLoggerForClass();

	Map data;

	// Map iterators = new HashMap();
	// Hashtable dataLine;
	ArrayList header;

	// saves current position in data Vector
	int currentPos, size;

	/**
	 * Constructor - takes no arguments.
	 */
	public Data() {
		header = new ArrayList();
		data = new HashMap();
		currentPos = -1;
		size = currentPos + 1;
	}

	/**
	 * Replaces the given header name with a new header name.
	 * 
	 * @param oldHeader
	 *            Old header name.
	 * @param newHeader
	 *            New header name.
	 */
	public void replaceHeader(String oldHeader, String newHeader) {
		List tempList;
		int index = header.indexOf(oldHeader);
		header.set(index, newHeader);
		tempList = (List) data.remove(oldHeader);
		data.put(newHeader, tempList);
	}

	/**
	 * Adds the rows of the given Data object to this Data object.
	 * 
	 * @param d
	 *            data object to be appended to this one
	 */
	public void append(Data d) {
		boolean valid = true;
		String[] headers = getHeaders();
		String[] dHeaders = d.getHeaders();
		if (headers.length != dHeaders.length) {
			valid = false;
		} else {
			for (int count = 0; count < dHeaders.length; count++) {
				if (!header.contains(dHeaders[count])) {
					valid = false;
				}
			}
		}

		if (valid) {
			currentPos = size;
			d.reset();
			while (d.next()) {
				for (int count = 0; count < headers.length; count++) {
					addColumnValue(headers[count], d.getColumnValue(headers[count]));
				}
			}
		}
	}

	/**
	 * Get the number of the current row.
	 * 
	 * @return integer representing the current row
	 */
	public int getCurrentPos() {
		return currentPos;
	}

	/**
	 * Removes the current row.
	 */
	public void removeRow() {
		List tempList;
		Iterator it = data.keySet().iterator();
		log.debug("removing row, size = " + size);
		if (currentPos > -1 && currentPos < size) {
			log.debug("got to here");
			while (it.hasNext()) {
				tempList = (List) data.get(it.next());
				tempList.remove(currentPos);
			}
			if (currentPos > 0) {
				currentPos--;
			}
			size--;
		}
	}

	public void removeRow(int index) {
		log.debug("Removing row: " + index);
		if (index < size) {
			setCurrentPos(index);
			log.debug("Setting currentpos to " + index);
			removeRow();
		}
	}

	public void addRow() {
		String[] headers = getHeaders();
		List tempList = new ArrayList();
		for (int i = 0; i < headers.length; i++) {
			if ((tempList = (ArrayList) data.get(header.get(i))) == null) {
				tempList = new ArrayList();
				data.put(headers[i], tempList);
			}
			tempList.add("");
		}
		size = tempList.size();
		setCurrentPos(size - 1);
	}

	/**
	 * Sets the current pos. If value sent to method is not a valid number, the
	 * current position is set to one higher than the maximum.
	 * 
	 * @param r
	 *            position to set to.
	 */
	public void setCurrentPos(int r) {
		currentPos = r;
	}

	/**
	 * Sorts the data using a given row as the sorting criteria. A boolean value
	 * indicates whether to sort ascending or descending.
	 * 
	 * @param column
	 *            name of column to use as sorting criteria.
	 * @param asc
	 *            boolean value indicating whether to sort ascending or
	 *            descending. True for asc, false for desc. Currently this
	 *            feature is not enabled and all sorts are asc.
	 */
	public void sort(String column, boolean asc) {
		sortData(column, 0, size);
	}

	private void swapRows(int row1, int row2) {
		List temp;
		Object o;
		Iterator it = data.keySet().iterator();
		while (it.hasNext()) {
			temp = (List) data.get(it.next());
			o = temp.get(row1);
			temp.set(row1, temp.get(row2));
			temp.set(row2, o);
		}
	}

	/**
	 * Private method that implements the quicksort algorithm to sort the rows
	 * of the Data object.
	 * 
	 * @param column
	 *            name of column to use as sorting criteria.
	 * @param start
	 *            starting index (for quicksort algorithm).
	 * @param end
	 *            ending index (for quicksort algorithm).
	 */
	private void sortData(String column, int start, int end) {
		int x = start, y = end - 1;
		String basis = ((List) data.get(column)).get((x + y) / 2).toString();
		if (x == y) {
			return;
		}

		while (x <= y) {
			while (x < end && ((List) data.get(column)).get(x).toString().compareTo(basis) < 0) {
				x++;
			}

			while (y >= (start - 1) && ((List) data.get(column)).get(y).toString().compareTo(basis) > 0) {
				y--;
			}

			if (x <= y) {
				swapRows(x, y);
				x++;
				y--;
			}
		}

		if (x == y) {
			x++;
		}

		y = end - x;

		if (x > 0) {
			sortData(column, start, x);
		}

		if (y > 0) {
			sortData(column, x, end);
		}
	}

	/**
	 * Gets the number of rows in the Data object.
	 * 
	 * @return number of rows in Data object.
	 */
	public int size() {
		return size;
	} // end method

	/**
	 * Adds a value into the Data set at the current row, using a column name to
	 * find the column in which to insert the new value.
	 * 
	 * @param column
	 *            the name of the column to set.
	 * @param value
	 *            value to set into column.
	 */
	public void addColumnValue(String column, Object value) {
		ArrayList tempList;
		if ((tempList = (ArrayList) data.get(column)) == null) {
			tempList = new ArrayList();
			data.put(column, tempList);
		}
		int s = tempList.size();
		if (currentPos == -1) {
			currentPos = size;
		}

		if (currentPos >= size) {
			size = currentPos + 1;
		}

		while (currentPos > s) {
			s++;
			tempList.add(null);
		}

		if (currentPos == s) {
			tempList.add(value);
		} else {
			tempList.set(currentPos, value);
		}
	}

	/**
	 * Returns the row number where a certain value is.
	 * 
	 * @param column
	 *            column to be searched for value.
	 * @param value
	 *            object in Search of.
	 * @return row # where value exists.
	 */
	public int findValue(String column, Object value) {
		List list = (List) data.get(column);
		int ret = -1;
		ret = list.indexOf(value);
		return ret;
	}

	/**
	 * Sets the value in the Data set at the current row, using a column name to
	 * find the column in which to insert the new value.
	 * 
	 * @param column
	 *            the name of the column to set.
	 * @param value
	 *            value to set into column.
	 */
	public void setColumnValue(String column, Object value) {
		List tempList;
		if ((tempList = (List) data.get(column)) == null) {
			tempList = new ArrayList();
			data.put(column, tempList);
		}

		if (currentPos == -1) {
			currentPos = 0;
		}

		if (currentPos >= size) {
			size++;
			tempList.add(value);
		} else if (currentPos >= tempList.size()) {
			tempList.add(value);
		} else {
			tempList.set(currentPos, value);
		}
	}

	/**
	 * Checks to see if a column exists in the Data object.
	 * 
	 * @param column
	 *            Name of column header to check for.
	 * @return True or False depending on whether the column exists.
	 */
	public boolean hasHeader(String column) {
		return data.containsKey(column);
	}

	/**
	 * Sets the current position of the Data set to the next row.
	 * 
	 * @return True if there is another row. False if there are no more rows.
	 */
	public boolean next() {
		return (++currentPos < size);
	}

	/**
	 * Gets a Data object from a ResultSet.
	 * 
	 * @param rs
	 *            ResultSet passed in from a database query
	 * @return a Data object
	 * @throws java.sql.SQLException
	 */
	public static Data getDataFromResultSet(ResultSet rs) throws SQLException {
		ResultSetMetaData meta = rs.getMetaData();
		Data data = new Data();

		int numColumns = meta.getColumnCount();
		String[] dbCols = new String[numColumns];
		for (int i = 0; i < numColumns; i++) {
			dbCols[i] = meta.getColumnName(i + 1);
			data.addHeader(dbCols[i]);
		}

		while (rs.next()) {
			data.next();
			for (int i = 0; i < numColumns; i++) {
				Object o = rs.getObject(i + 1);
				if (o instanceof byte[]) {
					o = new String((byte[]) o);
				}
				data.addColumnValue(dbCols[i], o);
			}
		}
		return data;
	}

	/**
	 * Sets the current position of the Data set to the previous row.
	 * 
	 * @return True if there is another row. False if there are no more rows.
	 */
	public boolean previous() {
		return (--currentPos >= 0);
	}

	/**
	 * Resets the current position of the data set to just before the first
	 * element.
	 */
	public void reset() {
		currentPos = -1;
	}

	/**
	 * Gets the value in the current row of the given column.
	 * 
	 * @param column
	 *            name of the column.
	 * @return an Object which holds the value of the column.
	 */
	public Object getColumnValue(String column) {
		try {
			if (currentPos < size) {
				return ((List) data.get(column)).get(currentPos);
			} else {
				return null;
			}
		} catch (Exception e) {
			return null;
		}
	}

	/**
	 * Gets the value in the current row of the given column.
	 * 
	 * @param column
	 *            index of the column (starts at 0).
	 * @return an Object which holds the value of the column.
	 */
	public Object getColumnValue(int column) {
		String columnName = (String) header.get(column);
		try {
			if (currentPos < size) {
				return ((List) data.get(columnName)).get(currentPos);
			} else {
				return null;
			}
		} catch (Exception e) {
			return null;
		}
	}

	public Object getColumnValue(int column, int row) {
		setCurrentPos(row);
		return getColumnValue(column);
	}

	public void removeColumn(int col) {
		String columnName = (String) header.get(col);
		data.remove(columnName);
		header.remove(columnName);
	}

	/**
	 * Sets the headers for the data set. Each header represents a column of
	 * data. Each row's data can be gotten with the column header name, which
	 * will always be a string.
	 * 
	 * @param h
	 *            array of strings representing the column headers.
	 */
	public void setHeaders(String[] h) {
		int x = 0;
		header = new ArrayList(h.length);
		for (x = 0; x < h.length; x++) {
			header.add(h[x]);
			data.put(h[x], new ArrayList());
		}
	}

	/**
	 * Returns a String array of the column headers.
	 * 
	 * @return array of strings of the column headers.
	 */
	public String[] getHeaders() {
		String[] r = new String[header.size()];
		if (r.length > 0) {
			r = (String[]) header.toArray(r);
		}
		return r;
	}

	public int getHeaderCount(){
		return header.size();
	}

	/**
	 * This method will retrieve every entry in a certain column. It returns an
	 * array of Objects from the column.
	 * 
	 * @param columnName
	 *            name of the column.
	 * @return array of Objects representing the data.
	 */
	public List getColumnAsObjectArray(String columnName) {
		return (List) data.get(columnName);
	}

	/**
	 * This method will retrieve every entry in a certain column. It returns an
	 * array of strings from the column. Even if the data are not strings, they
	 * will be returned as strings in this method.
	 * 
	 * @param columnName
	 *            name of the column.
	 * @return array of Strings representing the data.
	 */
	public String[] getColumn(String columnName) {
		String[] returnValue;
		Object o;
		List temp = (List) data.get(columnName);
		if (temp != null) {
			returnValue = new String[temp.size()];
			Iterator it = temp.iterator();
			int index = 0;
			while (it.hasNext()) {
				o = it.next();
				if (o != null) {
					if (o instanceof String) {
						returnValue[index++] = (String) o;
					} else {
						returnValue[index++] = o.toString();
					}
				}
			}
		} else {
			returnValue = new String[0];
		}
		return returnValue;
	}

	/**
	 * Use this method to set the entire data set. It takes an array of strings.
	 * It uses the first row as the headers, and the next rows as the data
	 * elements. Delimiter represents the delimiting character(s) that separate
	 * each item in a data row.
	 * 
	 * @param contents
	 *            array of strings, the first element is a list of the column
	 *            headers, the next elements each represent a single row of
	 *            data.
	 * @param delimiter
	 *            the delimiter character that separates columns within the
	 *            string array.
	 */
	public void setData(String[] contents, String delimiter) {
		setHeaders(JOrphanUtils.split(contents[0], delimiter));
		int x = 1;
		while (x < contents.length) {
			setLine(JOrphanUtils.split(contents[x++], delimiter));
		}
	}

	/*
	 * Deletes a header from the Data object. Takes the column name as input. It
	 * will delete the entire column.
	 * 
	 * public void deleteHeader(String s) {
	 *  }
	 */

	/**
	 * Sets the data for every row in the column.
	 */
	public void setColumnData(String colName, Object value) {
		List list = this.getColumnAsObjectArray(colName);
		while (list.size() < size()) {
			list.add(value);
		}
	}

	public void setColumnData(int col, List data) {
		reset();
		Iterator iter = data.iterator();
		String columnName = (String) header.get(col);
		while (iter.hasNext()) {
			next();
			setColumnValue(columnName, iter.next());
		}
	}

	/**
	 * Adds a header name to the Data object.
	 * 
	 * @param s
	 *            name of header.
	 */
	public void addHeader(String s) {
		header.add(s);
		data.put(s, new ArrayList(Math.max(size(), 100)));
	}

	/**
	 * Sets a row of data using an array of strings as input. Each value in the
	 * array represents a column's value in that row. Assumes the order will be
	 * the same order in which the headers were added to the data set.
	 * 
	 * @param line
	 *            array of strings representing column values.
	 */
	public void setLine(String[] line) {
		List tempList;
		String[] h = getHeaders();
		for (int count = 0; count < h.length; count++) {
			tempList = (List) data.get(h[count]);
			if (count < line.length && line[count].length() > 0) {
				tempList.add(line[count]);
			} else {
				tempList.add("N/A");
			}
		}
		size++;
	}

	/**
	 * Sets a row of data using an array of strings as input. Each value in the
	 * array represents a column's value in that row. Assumes the order will be
	 * the same order in which the headers were added to the data set.
	 * 
	 * @param line
	 *            array of strings representing column values.
	 * @param deflt
	 *            default value to be placed in data if line is not as long as
	 *            headers.
	 */
	public void setLine(String[] line, String deflt) {
		List tempList;
		String[] h = getHeaders();
		for (int count = 0; count < h.length; count++) {
			tempList = (List) data.get(h[count]);
			if (count < line.length && line[count].length() > 0) {
				tempList.add(line[count]);
			} else {
				tempList.add(deflt);
			}
		}
		size++;
	}

	/**
	 * Returns all the data in the Data set as an array of strings. Each array
	 * gives a row of data, each column separated by tabs.
	 * 
	 * @return array of strings.
	 */
	public String[] getDataAsText() {
		StringBuffer temp = new StringBuffer("");
		String[] line = new String[size + 1];
		String[] elements = getHeaders();
		for (int count = 0; count < elements.length; count++) {
			temp.append(elements[count]);
			if (count + 1 < elements.length) {
				temp.append("\t");
			}
		}
		line[0] = temp.toString();
		reset();
		int index = 1;
		while (next()) {
			temp = new StringBuffer("");
			for (int count = 0; count < elements.length; count++) {
				temp.append(getColumnValue(count));
				if (count + 1 < elements.length) {
					temp.append("\t");
				}
			}
			line[index++] = temp.toString();
		}
		return line;
	}

	public String toString() {
		String[] contents = getDataAsText();
		StringBuffer sb = new StringBuffer();
		boolean first = true;
		for (int x = 0; x < contents.length; x++) {
			if (!first) {
				sb.append("\n");
			} else {
				first = false;
			}
			sb.append(contents[x]);
		}
		return sb.toString();
	}
}
